1. Field of the Invention
The subject invention generally relates to composite articles having a piezoelectric layer. More specifically, the subject invention relates to composite articles having a piezoelectric layer formed of a polymer. The subject invention also relates to systems associated with the composite articles.
2. Description of the Related Art
Various articles having piezoelectric polymer layers and associated systems are well known in the art. Examples of such articles and systems are disclosed in U.S. Pat. No. 5,283,835 (the '835 patent).
The '835 patent discloses an article having a piezoelectric layer, preferably formed of a polymer such as polyvinylidine difluoride (PVDF). The piezoelectric layer is sandwiched between a pair of copper layers. Each conductive layer is overlayed by a nickel layer. The nickel layers are necessary to protect the copper layers from oxidation. The article of the '835 patent is deficient due to the nickel layer which adds complexity and reduces the flexibility of the article.
Furthermore, articles having piezoelectric layers sandwiched by metal layers tend to be cost prohibitive for a great many potential applications. Therefore, there remains an opportunity to provide articles which exhibit a piezoelectric property, resist oxidation, are flexible, and are cost efficient.